Y 3 Black Nylon One Piece Swimsuit Y 3 MATTEAU Racerback One Piece Nylon Swimsuit Matteau Balenciaga Black Nylon One Piece Swimsuit Balenciaga Balenciaga Black Nylon One Piece Swimsuit Balenciaga. The nylon One piece swimsuit by Ami Paris features an essential and contemporary silhouette. Crafted from nylon, the design is defined by its two tone look and a low cut back that enhances the silhouette. The tonal lining ensures comfort and fit, while the Ami de Coeur metal plate at the back adds a distinctive and iconic detail.